Penicillum citreonigrum XT20-134 (MCCC 3A00956) is a fungus with cytotoxic activity, derived from deep-sea sediment. Five new compounds, adeninylpyrenocine (1), 2-hydroxyl-3-pyrenocine-thio propanoic acid (2), ozazino-cyclo-(2,3-dihydroxyl-trp-tyr) (3), 5,5-dichloro-1-(3,5-dimethoxyphenyl)-1,4-dihydroxypentan-2-one (4), and 2,3,4-trihydroxybutyl cinnamate (5), together with 19 known compounds (6–24), were isolated from an ethyl acetate (EtOAc) extract of its fermentation. The structures of the new compounds were comprehensively characterized by high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS), 1D and 2D nuclear magnetic resonance (NMR). All isolates were evaluated for their cytotoxic activities. The heteroatom-containing new compounds 2 and 4 showed potent cytotoxicity to the human hepatoma tumor cell Bel7402 with IC50 values of 7.63 ± 1.46, 13.14 ± 1.41 μM and the human fibrosarcoma tumor cell HT1080 with IC50 values of 10.22 ± 1.32, 16.53 ± 1.67 μM, respectively.
To investigate structurally novel and anti-neuroinflammatory natural compounds from marine-derived microorganisms, the secondary metabolites of Aspergillus terreus Y10, a fungus separated from the sediment of the coast in the South China Sea, were studied. Three new compounds (2–4), with novel open-ring butenolide skeletons, were isolated from the ethyl acetate extract of the culture medium. In addition, a typical new butenolide, asperteretal F (1), was found to dose-dependently inhibit tumor necrosis factor (TNF-α) generation with an IC50 of 7.6 μg/mL. The present study shows the existence of open-ring butenolides, and suggests that butenolides such as asperteretal F (1) are a promising new anti-neuroinflammatroy candidate for neurodegenerative diseases.